Study On The Method Of Active Disturbance Rejection Control Of Two-way Cartridge Proportional Throttle Valve

With the development and progress of our country in the field of aerospace, machine tools, metallurgy, energy, petrochemical and vessel, the demand for heavy equipment and the requirement of the modernization level are higher and higher. cartridge proportional throttle valve is the basic key hydraulic elements in the large hydraulic systems. Further study the positon control charactoristics of cartridge proportional throttle valve and control strategy, it is important to improve the performance of the whole valve.Reaserch found that cartridge proportional throttle valve still exist some shotcomings: its control precision is affected by the nonlinearity of amplifier and electromagnet, valve core manufacturing error, and the factors of friction and flow force, so its dynamic reponse is slow. Under the condition of high pressure and big flow, load pressure step response starts with big overshoot, meanwhile, the flow stiffness and anti-interference ability are poor. Problems that how to improve the response speed of the vale, overcome the effects of flow force, maintain the repeatability of the main valve core position and the stability of control are needed to be solved. Aiming at the above problems, this paper focuss on the following research work:(1)The positon control system model and characteristics analysis of the electro-hydraulic cartridge valve. The method of mechanism modeling is used to carry on the modeling of electro-hydraulic cartridge valve, get the stiffness model. The relation between stiffness and control precision, anti interference performance is given,baced on the stiffness model. As the main interference source of cartridge valve, the variation of flow force is get with the help of CFD simulation software. Making an effective assessment about flow force, lays the foundation for the choice of the subsequent control strategy.(2)Aiming at the problems that slow response, interference of flow force and poor siffness, active disturbance rejection control is adopted. On the basis of the theory of active disturbance rejection control, the method of system identification is adopted to get the precise mathematical model of cartridge valve, in order to improve the performance of the system and design the accurate controller. With the help of MATLAB/Simulink software, build the simulation model of active disturbance rejection control, analyse simulation results, and lay the foundation for the experimental research. Aiming at the phenomena of high frequency oscillation, the active disturbance rejection is improved, and the control performance is analysed and compared with PID controller.(3)Experimental research has been carried on for the control characteristics of cartridge proportional throttle valve. This paper introduce the experimental system, data collection system and control system. The work of data collection is completed with the help of d SPACE controller. Experimental system is mainly to analyse the robutness of the change of active disturbance rejection controller parameters and the robutness of external disturbance, and compared with PID controller.